Lathe gouge sharpening tool

ABSTRACT

A sharpening guide for use with a chisel and a grinding wheel comprising a rod having a first end and a second end, a pivot assembly carried by the first end, a tool clamp attached to the pivot assembly and movable relative to the rod and adapted to retain the chisel, a base, and a base pivot for movably mounting the rod relative to the base whereby the base pivot is adapted to be mounted adjacent the grinding wheel. A method of sharpening a tool comprising the steps of locating a tool within a tool clamp, rotating the tool clamp toward a grinding wheel about a first axis until the tool is in contact with a grinding wheel, and rotating the tool clamp about a second axis to move the tool across the grinding wheel rotationally.

BACKGROUND OF THE INVENTION

1. Technical Field

The invention relates generally to holders for sharpening tools. More particularly, the invention relates to holders for sharpening gouges with a grinding wheel. Specifically, the invention relates to a gouge sharpening holder with multiple pivot axes, a guide cam, and an axially slidable mount to produce a precision grind.

2. Background Information

A chisel is a tool used for removal of material from work pieces such as stone, metal, and wood. The chisel generally includes two distinct ends. The first end is the material removal end, while the second end is the handle. The material removal end is made with various materials and designs depending on the task at hand. The handle end is shaped to allow the user to securely grasp the chisel and may include a hardened tip so that the chisel can be hit with a mallet or hammer to force the material removal end into and through the work piece. When the material end of the chisel is forced through the work piece, material removal and shaping is achieved.

Woodworking chisels are also immensely popular since wood can be manipulated easier than harder materials. Accordingly, a variety of chisels have been developed to accommodate the various needs of woodworkers. Among the specialized chisels are butt chisels, slick chisels, paring chisels, skew chisels, and carving chisels. The carving style chisel also includes a gouge chisel which is used to create a generally concave surface in the work piece. The gouge chisel creates a generally concave surface due to the chisel's U-shaped cross-section. A gouge chisel may be either incannel, where the cutting edge is within the U-shaped cross-section, or outcannel, where the cutting edge is on the outside surface the chisel.

With use, the leading edge of the gouge becomes dull and does not cut or remove material as efficiently. The woodworker must then proceed to sharpen the leading edge. This may be done free hand on a grinding wheel or on a sharpening stone. The use of a grinding wheel makes the sharpening procedure much easier and less time consuming. However, free hand sharpening of a gouge is difficult due to the precision needed in forming the leading edge along the U-shaped cross-section. Further, the grinding wheel in inherently dangerous because the user must apply pressure in the direction of the grinding wheel. If the tool slips off or catches an edge, the user could fall into the grinding wheel and cause severe injury to himself/herself.

SUMMARY OF THE INVENTION

The present invention broadly comprises a sharpening guide for use with a chisel and a grinding wheel comprising a rod having a first end and a second end, a pivot assembly carried by the first end, a tool clamp attached to the pivot assembly and movable relative to the rod and adapted to retain the chisel, a base, and a base pivot for movably mounting the rod relative to the base whereby the base pivot is adapted to be mounted adjacent the grinding wheel.

The present invention also broadly comprises a method of sharpening a tool comprising the steps of locating a tool within a tool clamp, rotating the tool clamp toward a grinding wheel about a first axis until the tool is in contact with a grinding wheel, and rotating the tool clamp about a second axis to move the tool across the grinding wheel rotationally.

BRIEF DESCRIPTION OF THE DRAWINGS

The preferred embodiments of the invention, illustrative of the best modes in which Applicants have contemplated applying the principles of the invention, are set forth in the following description and are shown in the drawings.

FIG. 1 is a side view of a preferred embodiment tool sharpening holder proximate a grinding wheel;

FIG. 2 is a top view of a lock and release mechanism of a preferred embodiment base taken generally about line 2-2 in FIG. 1;

FIG. 3 is a rear view of a preferred embodiment tool sharpening holder;

FIG. 4 is a cross-sectional view of a preferred embodiment tool sharpening holder taken generally about line 44 in FIG. 3;

FIG. 5 is a cross-sectional view of a preferred embodiment tool sharpening holder taken generally about line 5-5 in FIG. 1;

FIG. 6 is an enlarged side view of a preferred embodiment tool sharpening holder with a tool being aligned;

FIG. 7 is a cross-sectional view of a preferred embodiment tool sharpening holder taken generally about line 7-7 in FIG. 6;

FIG. 8 is an enlarged side view of a preferred embodiment tool sharpening holder with the holding portion being pivoted and axially directed towards the grinding wheel;

FIG. 9 is a top enlarged view of a preferred embodiment tool sharpening holder with a tool being sharpened on a grinding wheel when the holder is centrally located;

FIG. 9A is a top view of a preferred embodiment tool sharpening holder looking down the length of the holder when the holder is centrally located;

FIG. 10 is a top view of a preferred embodiment tool sharpening holder with a tool being sharpened on a grinding wheel when the holder is rotated fully counterclockwise;

FIG. 10A is a top view of a preferred embodiment tool sharpening holder looking down the length of the holder when the holder is rotated fully counterclockwise;

FIG. 11 is a top view of a preferred embodiment tool sharpening holder with a tool being sharpened on a grinding wheel when the holder is rotated fully clockwise;

FIG. 11A is a top view of a preferred embodiment tool sharpening holder looking down the length of the holder when the holder is rotated fully clockwise; and,

FIG. 12 is a side view of another preferred embodiment tool sharpening holder proximate a grinding wheel.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

At the outset, it should be appreciated that like drawing numbers on different drawing views identify identical, or functionally similar, structural elements of the invention. While the present invention is described with respect to what is presently considered to be the preferred embodiments, it is to be understood that the invention as claimed is not limited to the disclosed aspects.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood to one of ordinary skill in the art to which this invention belongs. Although any methods, devices or materials similar or equivalent to those described herein can be used in the practice or testing of the invention, the preferred methods, devices, and materials are now described.

The gouge sharpening tool holder of the present invention is indicated generally at 14, as is particularly shown in FIGS. 1 through 12. As particularly shown in FIG. 1, a preferred embodiment gouge sharpening tool holder 14 includes a base 16 and a rod 18. The gouge sharpening tool is secured to a table 20 or other suitable sturdy surface with bolts 22. A grinding wheel 24, includes an outer surface 26 which rotates about axis 25, is secured to the table and located proximate the tool holder.

In accordance with one of the main features of the present invention, base 16 includes a base beam 28 slidable within a mount 30. Averting to FIGS. 1, 2, and 3, the mount further includes a clamp 32 with a handle 34 and a lock 36. Lock 36 is preferably an enlarged cam with a larger diameter when handle 34 is rotated to a locked position and a smaller diameter when handle 34 is rotated to an unlocked position. In particular, lock 36 is tapered from a smaller diameter to a larger diameter to allow the clamp to lock base beam 28 in one position and unlock base beam 28 is a second position. Thus, base 16 is axially slidable through clamp 32 when the clamp is in the unlocked position and base 16 is fixed when clamp 32 is in the locked position.

Base beam 28 preferably includes a square cross-section and is oriented such that an edge of base beam 28 rests in the back inner portion of mount 30. Although the cross-section is preferably square, any shape that can be locked in position may be utilized.

Base 16 also includes a first end 38 a pair of spaced apart and parallel plates 39 having a pivot connection 40. Interposing first end 38 and base beam 28 is an enlarged member 42. A cam base 44 is complimentary shaped to fit over enlarged member 42 and still allow cam base 44 to slide along the outer surface of the enlarged member. Cam base 44 also includes a guide 46 pivotally mounted to cam base 44 at a thumb screw 48. In particular, when thumb screw 48 is loosened, guide 46 is capable of pivoting about the connection at thumb screw 48, and when the thumb screw is tightened, guide 46 is then fixed.

Viewing FIGS. 1 and 4, guide 46 includes a first plate 45 and a second plate 47. The first plate is rotationally secured to the enlarged member at thumb screw 48. The first plate spaces the second plate away from upwardly extending plate 43 and both enlarged member 42 and cam base 44. The second plate is generally perpendicular to first plate 45 and arranged to communicate with cam 62 (described infra). In particular, an outer surface 49 of second plate 47 is in frictional engagement with surface 63 of cam 62.

In accordance with another main feature of the present invention, base pivot 40 is attached to a housing 50. The housing is preferably rectangular or square in shape with a hole (FIG. 3) traversing the length of housing 50 and terminating at a boss 54 on a top surface and a boss 56 on a bottom surface. Preferably, housing 50 includes an upper bushing 53 with boss 54 and a lower bushing 55 with boss 56. Rod 18 is arranged to slide within hole 52 in bushings 53 and 55. A height adjuster 58 is secured to rod 18 and includes a bottom side located adjacent boss 54. The height adjuster is preferably a disc with a machined bottom surface to smoothly and evenly abut boss 54. Further, height adjuster 58 is removably secured around rod 18 and can be tightened or loosened at a bolt 60. Accordingly, height adjuster 58 can be located along the length of rod 18 as desired to control the height between housing 50 and the tool (described infra).

A cam 62 is located above height adjuster 58. Similar to the height adjuster, cam 62 surrounds rod 18 and is removable by loosening a bolt 64. Cam 62 is generally a right cylinder with a hole 66 traversing the length. In a preferred embodiment, hole 66 is offset from the center of cam 62 and allows non-uniform, or a parabola-like shape at an outer surface of the cam upon rotation of rod 18. Since the hole is offset, one side of cam 62 is further away from rod 18 than the opposing side of cam 62, thus meaning that rod 18 is spaced further away from plate in 47 some cam positions while being closer to plate 47 in other cam positions. Further, cam 62 rides against second plate 47 of guide 46 when the tool holder is pivoted towards grinding wheel 24 at pivot connection 40. Although the cam is shown and described as having a generally circular cross-section, it is within the spirit and scope of the invention to provide a cam with a variety of cross-sectional shapes.

As particularly seen in FIG. 3 and upward of cam 62, rod 18 may have a square cross-section portion at 68 of the rod. A second pivot connection 70 is located at the end of rod 18 that is distal base 16. Pivot connection 70 preferably includes a bolt 72 proximate a wall 73, a groove 74 in the end of rod 18, and a nut 76 welded to a wall 78. Pivot connection 70 includes walls 73 and 78 which extend upwardly and are spaced apart to receive a tool holding portion 80. Rotation at pivot connection 70 is prevented when bolt 72 is tightened at nut 76. Thus, pivot connection 70 allows tool holding portion 80 to rotate when bolt 72 is loosened and prevents rotation of the tool holding portion by compressing walls 73 and 78. 5 In a preferred embodiment, tool holding portion 80 includes a first side wall 82 and a second side wall 84 spaced apart at the top by an upper wall 86. First side wall 82 and second side wall 84 are angled inwards toward each other at the bottom of the tool holding portion and meet at and inside of pivot connection 70. Inner walls of first side wall 82, second side wall 84, and upper wall 86 form a cavity 88. At the lower portion of cavity 88, first wall 82 and second wall 84 are arranged in a V-shape to easily center the tool.

The tool is held in place by a bearing 90 which is in turn connected to a threaded rod 92 and a knob 94. Bearing 90 is preferably used because it will rotate slightly upon axial displacement and help insure that the tool is centered within the holding portion. The threaded rod passes through a threaded hole 96 in upper wall 86 of the tool holding portion. Accordingly, rotation of knob 94 rotates threaded rod 92 through hole 96 and axially displaces bearing 90 to selectively secure or release a tool.

Tool holding portion 80 further includes a tool alignment 98 connected to second side wall 84 in a preferred embodiment; however it is within the spirit and scope of the present invention to locate the tool alignment on any suitable portion of the tool holding portion, including first wall 82 or upper wall 86. Tool alignment 98 includes an alignment rod 100 with a first end 102 and a second end 104. A band 106 surrounds first end 102 and is slidable along the length of the alignment rod. First end 102 of rod 100 slides through a hole 107, complimentarily sized and shaped, in side wall 84. Since hole 107 is sized to allow only rod 100 to slide, band 106 prevents the alignment tool from extending beyond the length set by band 106. Thus, band 106 is set along the length of first end 102 such that rod 100 and second end 104 extend past a front side 108 of the tool holder and second end 104 provides the length that a tool to be sharpened must be inserted beyond the tool holding portion front side for proper alignment.

Averting to FIG. 4, rod 18 is shown traversing hole 52 in housing 50, height adjuster 58, and cam 62. Hole 66 of cam 62 is preferably offset from the center of cam 62 to match the desired contour of the tool (discussed infra). Further, guide 46 is arranged adjacent an outer surface 63 of cam 62 and rotation of rod 18 imparts eccentric rotation of cam 62 along second plate 47 of guide 46.

FIG. 5 is a cross-sectional view of cam base 44 disposed on enlarged member 42. Further base beam 28 is welded to enlarged member 42 in a preferred embodiment. Since cam base 44 is complimentarily shaped to enlarged member 42, cam base 44 is slidable along the length of the enlarged member. The cam base is fixed in place by rotation of screw 110 in a clockwise direction and released for movement in a counterclockwise direction. As described supra, thumb screw 48 allows adjustability of guide 46. A washer 112 separates upwardly extending plate 43 of cam base 44 and first plate 45 of guide 46, while another washer 112 separates thumb screw 48 and first plate 45 of guide 46.

Having described the structure of the preferred embodiment, a preferred method of operation will be described in detail and should be read in light of FIGS. 1 though 11, and particularly FIGS. 6 through 11.

As seen in FIG. 6, a tool 114 is shown being inserted through cavity 88 in the direction associated with arrows 116. Tool 114 also includes a first end 118 terminating in a tip 120. Band 106 is located on rod 100 in a position that allows rod 100 to extend beyond front side 108 and band 106 to rest against hole 107. Accordingly, tool 114 is inserted through cavity 88 until tip 120 is aligned with rod second end 104 to prepare the tool for sharpening. While the present invention is shown sharpening a gouge tool, any tool which requires sharpening with a contour may be utilized.

Next, FIG. 7 is a cross-sectional view of tool holding portion 80 with first end 118 of tool 114 secured by axial force in the direction associated with arrow 121 of bearing 90. Specifically, knob 94 is rotated and bearing 90 forces tool 114 downward by pushing on edges 122 and sets the tool in V-shaped cavity 88 formed by first wall 82 and second wall 84. When tool 114 is secured within tool holding portion 80, the tool is supported by bearing 90 on the top and by first wall 82 and second wall 84 on the bottom. After the tool is properly located and secured, tool alignment 98 is returned in the direction associated with arrow 124 to prevent damage to the tool alignment.

FIG. 8 exemplifies the next two steps, whereby base 16 and base beam 28 is axially moved in the direction associated with arrow 126. To this end, handle 34 is rotated (as seen in FIG. 2) to release clamp 32 and allow base beam 28 to slide within base mount 30. After the clamp is released, base beam 28 is moved in the direction of arrow 126 to locate tip 120 proximate grinding wheel outer surface 26. Next, tool sharpening holder 14 is pivoted about pivot connection 40 in the direction associated with arrow 128. Further, the user imparts a constant force in the direction associated with arrow 130 such that cam 62 and surface 63 are in constant communication with second plate 47 and surface 49 of guide 46. Thus the constant force in the direction of arrow 130 means that any rotation of rod 18 follows the contour of outer surface 63 of cam 62 and translates to a similar contour at tip 120 and tool first end 118.

FIG. 9 is a top enlarged view of the tool holder with tool 114 extending through cavity 88 and the tool holding portion located proximate grinding wheel 26. 1s Tip 120 is also located proximate grinding wheel outer surface 26. Having taken the above steps, the tool is now ready to be sharpened or ground after grinding wheel 24 is turned on and begins to rotate. FIG. 9A is a partial cross-sectional view looking down the tool holder and showing cam 62 off center from rod 18 and height adjuster 58.

As seen in FIG. 10, tool sharpening holder 14 is then rotated about rod 18 within housing 50 in the direction associated with arrow 132. In particular, the constant force in the direction of arrow 130 as described above is still applied, but a rotational force in the direction of arrow 132 is also applied. Cam 62 is arranged with outer surface 63 with a contour to the desired grind of tool end 118. In a gouge tool, the shape is generally parabolic and is achieved by maintaining tip 120 at constant axial distance from the grinding wheel outer surface 26. Thus, when the tool is rotated, the tip remains the same distance from the grinding wheel, but grinding occurs on a side of the tool end. Further, since outer surface 63 of the cam rotates eccentric from rod 18, the axial displacement of tip 120 and tool end 118 is controlled by outer surface 63 of cam 62 and allows a perfect parabola shape to be ground into the tool. Although the preferred embodiment is described with a parabolic, or U-shape, it is within the spirit and scope of the present invention as claimed to provide a cam with any shape that matches the desired tool tip contour. FIG. 10A is a partial cross-sectional view looking down the tool holder and showing cam 62 off center from rod 18 and being both rotated in the direction associated with arrow 132 and forced in the direction associated with arrow 130 into guide 46.

FIG. 11 is a top view of tool sharpening holder 14 being rotated in the direction associated with arrow 134, opposite arrow 132, to provide grinding to the opposite side of tool 114. FIG. 11A is a partial cross-sectional view looking down the tool holder and showing cam 62 off center from rod 18 and being both rotated in the direction associated with arrow 134 and forced in the direction associated with arrow 130 into guide 46.

In summary, the tool sharpening holder allows a precision grind of a tool with a non-uniform taper by securing the tool with only a single axis of rotation and rotating the tool sharpening holder cam against a guide to provide the desired tool contour.

Having now described the structure and operation of the first embodiment, only those portions of the remaining embodiment which are different from the first embodiment are described in detail. Likewise, similar numerals refer to similar parts throughout the various embodiments.

In accordance with a second embodiment of the invention shown specifically in FIG. 12 without a cam or guide, tool 114 is located within the tool holding portion 80. Pivotal connection 70 allows the user to adjust the angle of approach θ and to adjust where on the tool tip 120 the grinding wheel will remove material. Height adjuster 58 and rod 18 both operate in the same manner as the first embodiment.

In operation, the second embodiment locates tool 114 in the same manner as the first embodiment by using alignment tool 98. Next, pivotal connection 70 is adjusted to provide the correct angle of approach θ and base 16 is axially moved in the direction associated with arrow 136 after clamp 32 is released (which again functions identical to the first embodiment). Once the tool is located proximate and in slight contact with the grinding wheel, handle 34 is rotated to clamp beam 28 and base 16 in that position. Finally, tool 114 is rotated about rod 18 in the directions associated with arrows 132 and 134 as disclosed in the first embodiment to sharpen the tool.

Accordingly, the gouge sharpening tool is an effective, safe, inexpensive, and efficient device that achieves all the enumerated objectives of the invention, provides for eliminating difficulties encountered with prior art devices, systems, and methods, and solves problems and obtains new results in the art.

In the foregoing description, certain terms have been used for brevity, clearness, and understanding; but no unnecessary limitations are to be implied therefrom beyond the requirement of the prior art, because such terms are used for descriptive purposes and are intended to be broadly construed.

Moreover, the description and illustration of the invention is by way of example, and the scope of the invention is not limited to the exact details shown or described.

Having now described the features, discoveries, and principles of the invention, the manner in which the gouge sharpening tool is constructed and used, the characteristics of the construction, and the advantageous new and useful results obtained; the new and useful structures, devices, elements, arrangement, parts, and combinations are set forth in the appended claims. 

1. A sharpening guide for use with a chisel and a grinding wheel comprising: a rod having a first end and a second end; a pivot assembly carried by the first end; a tool clamp attached to the pivot assembly and movable relative to the rod and adapted to retain the chisel; a base; and, a base pivot for movably mounting the rod relative to the base whereby the base pivot is adapted to be mounted adjacent the grinding wheel.
 2. The sharpening guide as defined in claim 1 further comprising; a housing formed with a through hole for receiving the rod whereby the rod is rotatable relative to the housing; and whereby the housing is positioned intermediate the first and second end of the rod.
 3. The sharpening guide as defined in claim 2 further comprising a least one bearing carried by the housing adjacent the hole whereby rotation of the rod causes movement of the bearing
 4. The sharpening guide as defined in claim 2 further comprising: a pivot flange extending outwardly from the base; and, a pivot pin attached to the pivot flange and to the housing for providing pivotal movement between the base and the housing.
 5. The sharpening guide as defined in claim 4 wherein the pivot flange includes a pair of flanges for mounting the housing therebetween.
 6. The sharpening guide as defined in claim 2 further comprising a height adjuster attachable to the rod for operatively contacting the housing to prevent continued movement thereof in one direction.
 7. The sharpening guide as defined in claim 1 further comprising: a guide cam having an outer surface; a guide positioned adjacent the outer surface whereby one of the guide and guide cam is mounted on the rod; and whereby rotation of the rod causes the guide cam to move over the guide.
 8. The sharpening guide as defined in claim 7 in which movement of the guide cam relative to the guide is rotational.
 9. The sharpening guide as defined in claim 8 in which the guide cam is mounted on the rod and guide is carried by the base.
 10. The sharpening guide as defined in claim 9 in which the guide cam is movably mounted on the rod above the housing.
 11. The sharpening guide as defined in claim 10 in which the outer surface has a cross sectional configuration, and in which the cross sectional configuration is adapted to be similar to the chisel.
 12. The sharpening guide as defined in claim 1 further comprising a tool alignment carried by the tool clamp.
 13. The sharpening guide as defined in claim 1 in which the base pivot has a first axis and the pivot assembly has a second axis and in the rod has a third axis, and in which the third axis is perpendicular to at least one of the first axis and second axis.
 14. The sharpening guide as defined in claim 13 in which the first axis and the second axis are parallel.
 15. The sharpening guide as defined in claim 14 wherein rotation of the rod around the third axis causes axial rotation of the tool clamp.
 16. The sharpening guide as defined in claim 15 wherein rotation of the rod around the third axis causes rotation of the housing around the second axis.
 17. A method of sharpening a tool comprising the steps of: locating a tool within a tool clamp; rotating the tool clamp toward a grinding wheel about a first axis until the tool is in contact with a grinding wheel; and, rotating the tool clamp about a second axis to move the tool across the grinding wheel rotationally.
 18. The method as defined in claim 17 comprising the further steps of rotating the tool clamp about a third axis parallel to the first axis.
 19. The method as defined in claim 18 comprising the further steps of: moving a guide cam into contact with a guide; and, maintaining the contact between the guide cam and guide while the rod is rotated about the first axis.
 20. The method as defined in claim 19 comprising the further step of choosing a guide cam that is complimentary shaped to the profile of the tool.
 21. A sharpening guide for use with a chisel and a grinding wheel comprising: a rod having a first end and a second end; a tool clamp attached to the rod first end; a base having a receiving flange to secure the rod second end; and, wherein the rod rotates relative to the base.
 22. The sharpening guide of claim 21 wherein the tool clamp is adjustable relative to the rod.
 23. The sharpening guide of claim 21 wherein the base supports the rod on at least two locations of the rod.
 24. The sharpening guide of claim 21 wherein the rod is pivotable relative to the base.
 25. The sharpening guide of claim 17 further comprising the step of adjusting the tool clamp relative to a third axis prior to the step of rotating the tool clamp toward the grinding wheel. 